Miss-wire detector for pile wire looms



June 1964 c. a. ABELSMA ETAL 3,135,300

MISS-WIRE DETECTOR FOR FILE WIRE LOOMS Filed Dec. '7, 1962 2 Sheets-Sheet 1 \NVENTORS CORNELIS B. ABELSMA JAMES J. HIGGINS BY ,da w.

June 2, 1964 3,135,300

C. B. ABELSMA ETAL MISS-WIRE DETECTOR FOR PILE WIRE LOOMS 2 Sheets-Sheet 2 Filed Dec. 7, 1962 440v. 2 6OCY.

| lb k l l o. c. POWER SUPPLY 11 FIG. 3

MEASURING TIME AC AMPS LOOM CYCLE INVENTORS CORNELIS B.- ABELSMA JAMES J. HIGGINS BY W FIG.4

United States Patent 5,, 0 MISS-WIRE DETECTOR FOR PILE WIRE LOOMS Cornelis B. Abelsma'and James J. Higgins, Buena Vista, Va., 'assignors to James Lees and Sons Company, Bridgeport, Pa., a corporation of Delaware .FiledDec. 7, 1962, Ser. No. 243,156 4 Claims. (Cl. 139-336) This invention relates to electrical control systems and more particularly to an electrical miss wire detector for a transverse wire pile fabric loom.

Many devices have been proposed for stopping a pile fabric loom and particularly a carpet loom in the event that any one of several malfunctions occurs in the weaving cycle. For the most part, these detecting devices are of a mechanical nature or a mechanical device actuates a switch in an electrical control circuit. The present invention has the novel feature of sensing the amount of electrical current consumed in a weaving cycle and in the event of a variation in the current caused by malfunction, the loom is automatically stopped.

A primary object of the invention, therefore, is to provide electrical detecting means for monitoring the current consumed in the weaving cycle and closing a circuit to the loom knock-off motion, should the current curve vary from predetermined normal limits.

A further object of the invention is to provide means for detecting the absence of increased current consumed by the loom motor in pulling a pile wire together with means controlled thereby for stopping the loom.

Further objects will be apparent from the specification and drawings in which FIG. 1 is a fragmentary perspective showing the wire motion and hopper of a pile fabric loom in normal operation with the latch drawing the last pile wire in a series,

FIG, 2 is a perspective showing the latch failing to engage a pile wire which may be caused by a bent or broken head or some other circumstance preventing normal pulling of the wire,

. FIG. 3 is a diagrammatic sketch showing the control means and circuit of the present invention, and

FIG. 4 is a graph showing the current consumption of the motor during the critical portion of the weaving cycle.

Referring now more particularly to the drawings, a conventional transverse wire loom is provided with a hopper assembly 5 which reciprocates back and forth on the hopper rail 6. The hopper carries a spring loaded latch 7 which engages the head 8 of, the last one of a series of pile wires 9, 9. FIGURE 1 illustrates normal 6 operation in which the latch 7 has begun to pull the last pile wire in the set, whereas FIGURE 2 shows the malfunction condition commonly termed a miss wire in which, for one reason or another (for example a bent head 8), the latch 7 fails to pull the pile wire 9'. Since the structure shown in FIGURE 1 is entirely conventional and forms no part of the present invention, further description thereof is believed to be unnecessary.

In the ordinary operation of a carpet loom, the average motor current is on the order of five :amperes except during the time that a pile wire is being withdraw from the fabric. In this portion of the cycle the current increases to about seven amperes. In the event that no wire is withdrawn, for one reason or another, during the wire withdrawing portion of the cycle, the motor current remains at approximately five amperes. In order to detect this condition and to stop the loom accordingly, I provide a current transformer 10 in one side of the three phase 440 volt 60 cycle power supply 11 which operates the main loom motor 12. The secondary lines from the transformer 10 are carried to the primary winding 13 of a meter relay 14 through a cam controlled Patented June 2, 19.64

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switch 15. The holding winding 16 of meter relay 14 is connected to a direct current power supply 17, a.D.C. relay 18, cam controlled switch 19, and contacts 20. The contacts 18a of relay 18 are in a circuitconnected to the loom knock-off mechanism (not shown) .which is of the conventional well-known construction designed to stop the loom on the occurrence of any particular malfunction. A cam controlled switch 21 is aso in the knock-off circuit. The switches 15, 19, and 21 are controlled by the timing cam 22, the reset cam 23, and the knock-01f timing cam 24 respectively. These cams actuate cam followers 25, 26, and 27 associated with the switches 15, 19, and 21. All of the cams 22, 23, and 24 may be conveniently mounted on a common camshaft indicated schematically at 28.

In normal operation, the timing cam 22 closes switch 15 during the portion of the cycle in which there will normally be a current consumption higher than the current consumption for the remaining portion of the cycle. This higher consumption is shown in FIGURE 4 in the part of the graph marked 30. Closing of switch 15 energizes meter relay 14 to move arm 31 clockwise closing contacts 20. This in turn energizes relay 18 through closed switch 19 and the power supply 17. Energiza-.

tion of relay 18 opens normally closed contacts 18a so that when the knock-oft timing cam 24 closes switch 21, the circuit to the loom knock-0H? mechanism remains open and the loom continues to operate. In the event that the hopper fails to pull a wire, which in turn prevents an increase in current during the measuring portion 30 of the cycle, meter relay 14 fails to be energized and consequently relay 18 remains unenergized, thus permitting the normally closed contacts 18a to remain closed. In this situation as switch 21 closes due to the turning of cam 24, the circuit to the well-known knockolf is completed, and the loom stops. The meter relay 14 is in effect a galvanometer which can be adjusted so that the contacts 20 will not be closed unless a preset current passes through winding 13. In this way the meter can be adjusted so that, if the current remains at approximately five amperes as shown at 25 in FIGURE 3, contacts 20 will not be closed. In normal operation the reset cam 23 breaksthe circuit to relay 18 thus deenergizing the relay and opening contacts 18a. This also releases contacts 20 in readiness for the next cycle.

While the present invention has been described in connection with the detection of a miss wire malfunction in a carpet loom, it will be understood that it may be applied to many similar devices in which it may be desired to detect the failure of a peak current consumption to occur in any portion of a cycle. There are no mechanical parts to be replaced or to wear and to require adjustment after the initial setting. This eliminates main tenance problems and false stops.

Having thus described my invention, we claim:

1. A miss pile wire detector for transverse pile wire looms and the like comprising a main motor having fluctuating current consumption during various portions of a cycle, an electrical circuit for detecting peak current consumption during a portion of the cycle, a cyclically controlled timing switch in said circuit for closing the circuit during the portion thereof to be measured, a relay in said circuit, a switch controlled by said relay to be closed when a predetermined current energizes the relay, a second circuit closed by said switch, a relay in said second circuit, a knock-01f circuit for the loom, a switch in said knock-elf circuit controlled by said second relay, and a cam controlled switch in said knock-off circuit.

2. Apparatus in accordance with claim 1 having a reset cam in the second circuit.

cluding a reciprocating hopper for Withdrawing one of said pile wires from a fabric being Woven, an electric motor for driving the loom, means for detecting the load in amperes drawn by said motor during the portion of the loom cycle in which said wire is withdrawn, and means associated with said detecting means for stopping the loom in the event th at the current drawn by the motor during the Wire withdrawing portion of the cycle fails to attain its normal value.

References Cited in the file of this patent UNITED STATES PATENTS Spendlove July 21, Spendlove June 5, Wilson Aug. 6, Hyde Nov. 14, 

1. A MISS PILE WIRE DETECTOR FOR TRANSVERSE PILE WIRE LOOMS AND THE LIKE COMPRISING A MAIN MOTOR HAVING FLUCTUATING CURRENT CONSUMPTION DURING VARIOUS PORTIONS OF A CYCLE, AN ELECTRICAL CIRCUIT FOR DETECTING PEAK CURRENT CONSUMPTION DURING A PORTION OF THE CYCLE, A CYCLICALLY CONTROLLED TIMING SWITCH IN SAID CIRCUIT FOR CLOSING THE CIRCUIT DURING THE PORTION THEREOF TO BE MEASURED, A RELAY IN SAID CIRCUIT, A SWITCH CONTROLLED BY SAID RELAY TO BE CLOSED WHEN A PREDETERMINED CURRENT ENERGIZES THE RELAY, A SECOND CIRCUIT CLOSED BY SAID SWITCH, A RELAY IN SAID SECOND CIRCUIT, A KNOCK-OFF CIRCUIT FOR THE LOOM, A SWITCH IN SAID KNOCK-OFF CIRCUIT CONTROLLED BY SAID SECOND RELAY, AND A CAM CONTROLLED SWITCH IN SAID KNOCK-OFF CIRCUIT. 